Blast-furnace top.



No. 700,963. Patented May 27, I902.

P. MEEHAN. BLAST FURNACE TOP.-

(Application filed Apr. 12, 1901.)

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UNTTEE STATES PATENT OFFICE.

PATRICK MEEHAN, OF LOWELLVILLE, OHIO.

BLAST-FURNACE TO P.

SPECIFICATION forming part of Letters Patent No. 700,963, dated May 27,1902.

Application filed April 12, 1901.

T0 aZZ whom, it may concern:

Be it known that I, PATRICK MEEHAN, a resident of Lowellville, in thecounty of Na honing and State of Ohio, have invented a new and usefulImprovement in Blast-Furnace Tops; and I do hereby declare the followingto be a full, clear, and exact description thereof. I 7

My invention relates to the construction of blast-furnace tops, and hasfor its object to improve the construction of furnace -t0ps whereby afree expansion and contraction of the masonry shaft is permitted withoutdisturbing the furnace-top, whereby the life of the top of the stack isgreatly increased, whereby the amount of fine ore carried out by thegases is reduced, and whereby damage due to explosions is greatlydecreased, and in general to increase the strength and durability offurnace-tops.

Heretofore in blast-furnaces it has been the practice to place thegas-outlet ports to which the downcomer is connected, in the upperportion of the side wall of the furnace, and the topwas fiat and restedupon the top of the masonry shaft. This construction not only weakenedthe top of themasonry shaft, but as the gases'were taken out throughsaid side walls they would carry with them a considerable amount of thefine ores, and the expansion of the masonry shaft was liable to lift ofithe top of the furnace resting thereupon. i

Furthermore, any slight excess of pressure in the furnace-chamber wouldalso lift the top off the shaft, thereby necessitating frequentrepairs,and whenever an explosion occurred the damage to the furnace-top was very great, for.

the reason that the hopper projecting through the top of the furnace didnot extend down i into the stack sufficiently far to prevent the SerialNo. 55,505. (No model.)

into the stack to such a distance that the stock cannot be filled inclose up to the top, thereby leaving at all times a considerable spacein said globe-shaped top and above the stock-line, into which space thegases can expand upon explosion, the gas-ports connected tothedowncomers extendingthrough said globe-shaped top, so that themasonry wall of the shaft is not weakened thereby, and said ports thusbeing a considerable distance above the lower end of the hopper, wherebythe amount of fine ores carried out by the gas is greatly reduced.

My invention also comprises certain improvements in the manner ofsupporting this globe-shaped top on the shell of the stack, so as topermit free expansion. of the masonry walls of the stack, and alsocertain details in construction of the top of the wall of the shaftwhich will permit this free expansion and greatly increase the life ofsaid stack.

In the accompanying drawings, Figure 1 is a vertical section through thetop of the furnace. Fig. 2 is a side elevation of a portion of thehopper. Fig. 3 is a horizontal section of the same on the line 3 3, Fig.2. Fig. 4is a horizontal section through several of the hollow blocks ontop of the masonry shaft, and Fig. 5 is a vertical sectional detail of amodification of the upper part of the stack.

The shaft of the furnace is constructed as usual and comprises themasonry shaft 1, the metallic shell 2 around the same, and thecomparatively soft or porous compressible material 3, such as furnace-cinder, placed between the masonry shaft 1 and the outer shell 2in order to permit radial expansion and contraction of the masonryshaft. .of the shaft 1 is formed of one or more tiers The top of hollowblocks, (the drawings showing two such tiers or blocks;) but more orless than two may be used, if desired. These blocks are preferablyformed of 'cast metal and will .not wear away easily by the ore fallingon the circular shape ofthe stack. The blocks 5 of the upper tier aresubstantially triangular in vertical cross-section, thereby forming aninclined top 6 for the stack. The various blocks in the several tiersare provided with interlocking tongues and grooves, as shown at 7, andsimilar tongues and grooves are formed between the blocks of the severaltiers, as shown at 8, for the purpose of holding them securely in place,and said blocks are provided with internal transverse webs or braces 9to strengthen the same. The blocks 5 of the upper tier are provided attheir upper ends with the downwardly-projecting lips 10, which take overthe upper end of the shell 2 of the stack, whereby said blocks are heldin place, but the connection being such that the blocks can ride up anddown on said shell as the masonry shaftl expands and contracts.

The top 11 of the furnace is substantially globe-shaped, as shown, andsprings from the outer Wall of the stack, so that an enlargedsubstantially globe-shaped chamber 12 is formed at the top of the stack.This top comprises the globe-shaped metal shell 13,which is secured tothe shell 2 of the stack a short distance below the upper edge of thelatter and is provided with the refractory lining 14:, which extendsdown into the space between the shell 2 and the shell 13, as shown at15, a slight clearancespace 16 being left between the overhanging lipsof the blocks 5and said lining, so that there is no friction betweensaid parts in order that the stack 1 may expand and contract freelywithout affecting the top. Extending through the walls of thisglobe-shaped top are the gas-ports 17, to which are connected thedowncomers 18, said ports being provided at their tops with theexplosion-doors 19, as is common in blast-furnaces. The lower walls 20of these gas-ports are substantially on a line with the inclined face 6of the top of the stack, so that a straight and free passage of thegases out of the furnace-chamber to the downcomers and explosion-doorsis provided.

Extending through the top of the furnace is the hopper 21, which iscomposed of a series of segments 22, which, as shown in Figs. 2 and 3,comprise a quadrant of a circle; but they may comprise any other segmenteither greater or less than a quadrant, if desired. These segments formthe side walls of the hopper, and they are provided at their lower endswith the internal flanges 23, upon which rests the funnel-shaped bottom24, said bottom having an opening which is closed by the usual bell andbeing held from rising under the pressure of the gases by the detachablerods 26. By this construction it is possible to raise the bell andbottom of the hopper out of the furnace by merely removing the rods 26.The segments 22 are each cored out or cast about suitable pipes, whichextend down into the same, as at 27 and 28, and along the lower edge ofsaid segment and through the flange 23 thereof, being connect- To theuped at their outer ends, as at 29.

per ends of these pipes 27 and 28 suitable water connections are made,so that water will flow in, for instance, down through the pipe 27 andaround through the flange 23 to .the end 29 and back and up through thepipe 28 to the outlet. This construction effectually water-cools thelower edges of the segments 22 and prevents the same from burning .out.These segments are also provided with the external vertical ribs 30 andthe horizontal ribs 31, upon the latter of which vrest the lower ends ofbrackets 32, which are bolted to the ribs 30 of said segments andconnected to the furnace-top 13 and embedded in refractory material 33.This construction provides a strong and well-braced top for the furnace.

The hopper 21 projects down into the furnace-chamber, so that itsoutlet-opening, as at 34, is somewhat below the top of the stack, andthis prevents the feeding of so much stock into the furnace that it willcome close to the top of the furnace, whereby an extensive open space orchamber is always insured. The globe-shaped top 11, furthermore, springsoutwardly from the exterior of the stack and at a point which 'is butslightly below the outlet from the hopper, so that the largest diameterof the globe-shaped chamber in the top is above the outlet from thehopper, thereby increasing the space or chamber existing at the top ofthe furnace. Consequently when an explosion of gases occurs they willexpand into this chamber or space, thereby greatly reducing theliability of damaging the top of the furnace. Furthermore, the gas-ports17 are so located in the top as to be in a straight line with theinclined top face 6 of the stack, whereby a straight path is providedfor such expanding gases to the explosion-doors 19, thereby furtherreducing the liability of damaging the top during explosion. Thesegasports 17 are located a considerable distance above the outlet of thehopper, so that any fine ores which may be carried upward by the gaseswill have ample opportunity to again settle and return to the furnace-chamber before reaching the downcomers 18. The straight faces 20 of thegas-ports and corresponding faces 6 on the top of the stack prevent thelodgment of these fine ores, and thus facilitate their return to thefurnace-chamber. As a further aid to prevent the rise and escape of thefine ores the top of the stack may be provided with an internal annularprojection, as shown at 35, Fig. 5, which is preferably formed bysuitably shaping the blocks 4 and 5 when the latter are used; but incase no hollow blocks are used on the top of the furnace the masonrywalls will be arched in the manner shown.

. What I claim as my invention, and desire to secure by Letters Patent,is

1. A blast-furnace having ashaft, a globeshaped top on said shaftproviding a substantially globe-shaped chamber having an unobstructedannular passage to the furnacechamber, and a hopper projecting throughsaid top and extending down into the globeshaped chamber with itsdischarge end below the largest diameter of said globe shaped chamber,whereby an enlarged space is provided to allow for the expansion ofgases in an explosion.

2. A blast-furnace having a shaft, a globeshaped top springing from saidshaft providing a substantially globe-shaped chamber having anunobstructed annular passage to the f urnace-chamber,a hopper projectingthrough said top and extending downward into the globe-shaped chamberwith its discharge end below the largest diameter of said globeshapedchamber, whereby an enlarged space is provided to allow for theexpansion of gases in an explosion, a gas-port extending through saidglobe-shaped top, and a downcomer connected to said port.

3. A blast-furnace having a masonry shaft, a metal shell around saidshaft,a globe-shaped top springing from said shell and providing asubstantially globe-shaped chamber having an unobstructed annularpassage to the furnace -chamber, and a hopper projecting V through saidtop and extending down into the globe-shaped chamber with its dischargeend below the largest diameter of said globe shaped chamber,whereby anenlarged space is provided to allow for the expansion of gases in anexplosion.

4. A blast-furnace having a masonry shaft, a metal shell around saidshaft, a globe-shaped top springing from said shell and providing asubstantially globe-shaped chamber having an unobstructed annularpassage to the furnace-chamber, a hopper projecting through said top andextending downward into the globe-shaped chamber with its discharge endbelow the largest diameter of said globeshaped chamber,a gas-portextending through said globe-shaped top, and an explosion-door at theouter end of said gas-port.

5. A blast-furnace having a masonry shaft, a metal shell around saidshaft, aglobe-shaped metal top springing from the outside of said metalshell below the top thereof, and a refractory lining for saidglobe-shaped top, the lower edge of said lining projecting down betweenthe globe-shaped metal top and the metal shell for the stack and lyingoutside the latter, whereby free expansion of the masonry shaft ispermitted.

6. A blast-furnace having a masonry shaft, a metal shell around saidshaft, the top of said shaft being formed of blocks having lips whichare hooked over said shell, a globeshaped metal top springing from theoutside of said metal shell below the top thereof, and a refractorylining for said globe-shaped top, the lower edge of said liningprojecting down between the globe-shaped top and metal shell for thestack and lying out of contact with the overhanging lips of the blockson the top of the shaft.

7. A blast-furnace having a masonry shaft provided with an inclinedupper face, a metal shell around said shaft, a globe-shaped topspringing from said shell and providing a substan tially globe-shapedchamber having an unobstructed annular passage to the furnacechamber, ahopper projecting through the top and extending downward in theglobeshaped chamber with its discharge end below the largest diameter ofsaid globe shaped chamber, a gas-port extending through saidglobe-shaped top and substantially in line with the inclined upper faceof the masonry shaft, and an explosion-door at the outer end of saidgas-port.

8. A blast-furnace having a masonry shaft the top of which is formed byone or more tiers of hollow cast-metal blocks, said blocks being belowthe discharge end of the hopper and the gas-ports.

9. A blast-furnace having a masonry shaft the top of which is formed byone or more tiers of interlocking hollow blocks.

10. A blast-furnace having a masonry shaft the top of which is formed ofclosed hollow cast-metal blocks provided with inclined upper faces, saidblocks being below the discharge end of the hopper and the gas-ports.

11. Ablast-furnace havinga masonry shaft, and a metal shell around saidshaft, the top of said shaft being formed of hollow blocks having lipswhich hook over said shell.

In testimony whereof I, the said PATRICK MEEHAN, have hereunto set myhand.

PATRICK MEEHAN. Witnesses:

G. KREMER, ROBERT C. TOTTEN.

